1. Field of the Invention
The presenting invention relates to method and device for controlling a video recording attribute such as a frame rate and/or an exposure value to suitably record a video depending on a velocity of an object detected by a camera module.
2. Description of the Related Art
In general, a surveillance camera has to record a video for a considerable long time and thus requires a data storage space for storing a lot of data. However, since the storage space cannot be infinitely extended due to restrictions in cost, space, and the like, it is necessary to compress a video as much as possible so as to store the video in a definite storage space and thus to control a compression rate or a frame rate so as to maintain the performance of the surveillance camera.
The frame rate at which a human being can recognize a natural motion is about 30 fps (frame per second). Accordingly, in the past, the surveillance camera was set to perform a video recording operation only at a constant frame rate (for example, 30 fps).
However, the video recorded by the surveillance camera may include only a stationary background in which no variation exists in a surveillance area or may include an object moving at various velocities. That is, the object existing in the video recorded by the surveillance camera may move at various velocities.
In the surveillance camera recording a video only at a constant frame rate, when an object moving at a low velocity exists or no moving object exists in the surveillance area, a lot of video data are generated unnecessarily to waste the storage space. When an object moving at a high velocity and not being accurately photographed at the constant frame rate exists in the surveillance area, it is not possible to accurately record the object and thus to properly exhibit the performance as a surveillance camera.